Dental engine handpiece



. 5, 1932. R, Q ANGELL LSZSQ DENTAL ENGINE HANDPIECE Filed Aug. 20, 1928 2 Sheets-Sheet l S14/vento@ R. c. ANGELL. ,8?19,289

DFM'TAL ENGINE HANDPIECE Jam 5, 1932.

Filed Aug. 20, 1925; 2 Sheets-Sheet 2 Patented Jan. 5, 1932 l, I UNITED STA-TES PATENT i OFFICE ROBERT o. ANGELIJ, 0E PRINCE BAY, NEW YORK', AssIGNoRToTHE s. s. WHITE DENTAL j MANUFACTURING ooI/IPANY, A CORPORATION 0E PENNSYLVANIA Y DENTAL ENGINE HANnPIEoE Application filed August 20, 1928. Serial No.. 300,657.

My invention relates `particularly to that class of handpieces that are usually employed inconnection with. dental .engines and in which the rotating parts include chuck mechanism arranged to detachably engage drills,'

burs, grinding tools, land suchimplementsas arecommonly employed in dentistry; .and in repair, and permit theparts. to be convenient# v `Other objects of my invention .are toprvo-k vide a dental engine handpiece witlrexte`rirly disposed adjustingmeans conveniently' accessible for manipulation by n theV operator,

. whereby the outer casing or shaft maynot only Vbe secured in operative position, but be adjusted to prevent end shake orchatter and to take .up any wear'on the spindle and its bearings.. f Y

invention comprehendsa tooldriving spindle comprising a unitary hollow struc..- ture extending.` throughout the handpiece and affording a mounting upon which the' driving cordrpulley is directlymonnted. My invention also includes all of the various novel features of construction and' arrangement. las hereinafter more Adefinitely specified. p.. 4.

In. the accompanying drawings, Figure l isa side elevational Viewy of. a handpiece con# structed in accordance with my invention,at tached to a wrist joint' connection; Fig. 2li's a central vertical longitudinal sectional elevational view of the handpiecestructure shown 'inFig 1,4the spindle being shown in eleva.-

tion .fer convenience V.of illustration;fFig.. 3 .is an enlarged fragmentary sectional elevational View of therear end `of the. handpiece :shown in Figs. l and 2 taken on theline; 3.--3 in. Fig. 2; Fig. iis a side. elevational viewv of.

the split screw-collar shown: in-.section in Figs. ,2 and 3 and in elevation in lp; Fig. 5 1s a transverse vertlcal sectional view .Sheath 7.v

der, 21 by the thumb-semer cenet 22 hav; ing'its shank .23. in threadedengagement with of split screw collar taken on the vline 5-.5 in Fig, 4; Fig. 6 is a longitudinal sectional view of the handpiece with the sheath removed, the tool and chuck rod being shown in elevation forV convenience of'v illustration Figr 7, isa centralvertical longitudinal sectional view, taken on .the'line-Y in Fig. 2; ofthe.. forward end ofthe handpiece. shown in Figs'. 1 and 2, the chuck rod being shown in elevation for convenience of illustration; Fig. 8 is a perspective view of thechuclr rod and thecollet through which it is longitudinally adjusted; Fig. 9 is a perspective view of theA followe'ror plunger for effecting con? Atraction or expansion ofthe chuck; and Fig.

10,.;is a perspective view of thesplit chuck shownin.Figs.Y 6`and7. i j Insaid g-.uresthe wrist jointv framel comprises the tubular bearing 2 in which the back or inner end portion of the spindle 3 is mounted for rotation7 and which affords a forwardly projectingtubul'ar telescopic support 5 Vfor the expandedrearl end portion"6 ofthe .j Said spindle-3 is provided with *and annu-lar integral collar-9 forming the lshoulder l0 which bears against thefforwardly Vproject'- f ing end of thatpart ofy the bearing 2 which forms the sheath rsupport 5 and which takes the aXial workingthrust of said spindle. A

The forward end portion 12of the spindle 3 is conically tapered and is rotatably fitted in the similarly tapered bearing'. 13 atfthe Vforward end of the sheath 7 which'is Yprolvided'with the axially disposed aperture 15 `through which tools, such as the bur lfshown in'l Fig. 6, may be inserted and withdrawn.

` Y The rear endof the? spindle3` projects A beyond the frame bearing 2 and is reduced to form the hub' 17K for thefdriving. cordpulley- I9; which is prevented' from relative rotation secured thereon and forced against the shoulthe threads'25 in tlierea-rend-of the bore 26 ofthe spindle 3.. e The forward end ofthe bore V2,6.is conically .tapered towardgtlie'faxial tool receiving 'aperture-.27."l and affords a' conical forward `thereon by theflat su'rf'acesQOyand whichis seat 29 for the longitudinally split chuck 30 through the bore 31 of which the shank 32 of the tool 16 is extended, as shown in Fig. 6.

As best shown in Fig. 7 the split chuck 30 is normally expanded to receive the tool shank and has its opposite ends formed conical and respectively arranged to'engage the conical seat 29 in the bore of the spindle 3 and the conical seat 35 in the forward end of the follower or plunger 36 which is disposed for axial movement in the bore 26 and which is arranged to be forced forward to effect contraction of the chuck 30 by the axial adjustment of the chuck rod 37.

As best shown in Fig. 6, the chuck rod 37 extends through the collet 22 and is provided with the knurled head 39 by which it may be conveniently rotated to effect axial movement of the plunger 36 either by thrusting it outwardly to cause contraction of the chuck 30 to engage the tool, or by withdrawing it inwardly to permit normal expansion of said chuck and consequent release of said tool.

The chuck rod 37 terminates in a rounded forward end lO so as to bear at an axial point on the plunger 36, and is maintained in concentric relation with the spindle bore 26 by the collar ll which is integral with said chuck rod and preferably disposed adjacent to its outer end.

The sheath 'l' may for convenience `be provided with a coverin 43 of-r hard rubber, bakelite or other suitable material, that will not readily slip in the hand of the operator, and the expanded rear end of the sheath terminates in a radially extended flange Vl5 which, when said sheath is in its working position, is spaced from the shoulder i6 formed on the frame by the threaded boss 47.

To the threaded boss l? is secured the nut 50 having the knurled peripheral regionbl by which it may be conveniently rotated. Said nut is cooperative with Vthe split collar 53 which is mounted to freely rotate on the sheath 7 against the flange 45 in threaded engagement with said nut to effect axial adjustment of said sheath 7 on said' spindle 3 with respect to said frame l, whereby said sheath may be adjusted to vary the closeness of fit of theconical or tapered bearing surfaces at the forward end of said sheath and spindle, or be backed off to permit the'sheath to be removed therefrom.

The collar 53 may preferablybe provided with the transverse split 55, and the longitudinally disposed split 56 extended through the thr-eads thereofand arranged-to render the collar so. resilient as to effect a binding action when engaged with the nut 50 to prevent its accidental displacementby reason of possible vibrationnof the handpiece structure.

From the foregoing, it will be obvious that the inner adjustment of the sheath 7 is limited by the cooperation of the conical bearing surface 13 with the similarly tapered surface on the spindle 3,l so that any wear on said surfaces may be readily taken up by shifting the sheath inwardly and causing the flange l5 to more nearly approach the shoulder 46. rlhis may be effected by merely rotating the collar 53 in threaded engagement with the nut 50.

My invention is advantageous in that the handpiece may be taken `apart and 'the separate parts independently removed by the hands ofthe operator without the aid of tools; for instance, the sheath 7 may be removed by holding the frame in one hand while rotating the' nut 50 with the split collar 53 between the thumb and finger of the other hand, and the spindle 3 may be removed from the frame l and the parts thereof separated therefrom by merely removing the thumb screw or collet 22 from said spindle.

Furthermore, a plurality of sheaths may be provided which may be interchangeably engaged with the spindle. Thus, it will be seen that a properly sterilized sheath may be readily substituted after operation upon each individual patient.

l do not desire to limit my invention to the precise details of construction and arrangement as herein set forth, as it is obvious that various modifications may be made therein without departing from the essential features of my invention as defined in the appended claims.

l-lavingthus described my invention, I

claim l. A dental handpiece comprising a frame,

a spindle rotatably mounted in said frame and having a` bearing surface, a sheath for said spindleA having a complementary bearing surface forming a Vjournal in which said spindle rotates, and exteriorly operable means conveniently actuated abouti-he axis of said sheath arranged to adjustably vary the closeness of ht between said surfaces.

2. A dental handpiece. comprisinfT a frame, a spindle rotatably mounted in said frame Aand having a tapered bearing surface, a sheath for said spindle having a journal bearing vsurface cooperative with the bearing surface on said spindle, and exteriorly operable means conveniently actuated in the direction of the axis of said sheath arranged to adjustably vary the closeness of fit between said surfaces. f

' 3. 'A dental handpiece comprising a frame, a spindle rotatably mounten in said frame and having a tapered bearing surface, a sheath for said spindle having a journal bearing surface cooperative with the bearing surface on said spindle and arranged to limit the inner'movement ofv said sheath on said spindle, and exteriorly operable means adjustable coa-xial'with said sheath arranged to adjustably varythe closeness of fit between said surfaces.

bracing said sheath arranged to adjust it axially with respect to said frame and spindle and thereby compensate for Wear on said bearing. Y

5. A dental handpiece comprising'a frame having threaded means, a spindle rotatably mounted in said frame and having a tapered bearing region, a sheath for said spindle having a. bore provided with a'surface cooperative with said tapered bearing region and serving asa bearing therefor, and means coaxial with said sheath and cooperative with said threaded means arranged to adjust said sheath axially with respect to'said frame and spindle and thereby cause said bearing sur-.l

faces to be engaged with any desired degree of closeness.

6. A dental handpiece comprising a frame, a nut in threaded engagement with said frame and having a threaded extension projecting forwardly, ra vspindle rotatably mounted in said frame and having a tapered region, a sheath for said spindle having a bore provided with a surface lcooperative with said tapered region and serving as a bearing therefor, and a collar in threaded engagement with said threadedl extension arranged to eect axial adjustment of said sheath with respectto said frame and spindle Y and thereby take up on said bearing.

7. A dental handpiece.comprisinga frame, a nut in threaded engagement with said frame, a spindle rotatably mounted in` said frame and having a tapered region, a sheath for said spindle having a bore provided with a surface cooperative withsaid tapered region and serving as a bearing therefor, and

having a flange at its inner end, and a collar rotatably mounted on said sheath in threaded engagement with said nut arranged to engage said flange and adjust said sheath axially with respect to said frame and spindle and thereby take up on said bearing.

8. A dental handpiece comprising a frame provided with threaded means, a spindle rotatably mounted in said frame and having a tapered region, a sheath for said spindlev having a bore provided with a surface coop-- erative with said tapered region and serving the bearing therefor and having a flange at its inner end, and a split collar rotatably mounted on said sheath in threaded engagementwith said threaded means arranged to engage'said flange and adjust said sheath axially with respect to said frame andspin-v die and thereby take up on said bearing.

9. A dental handpiece comprising a frame affording .a bearing, a spindle rotatably mounted in said frame and A,having a collar abutting against saidframe, adriving cord pulley mounted on said spindle exterior to 'saidfframe, and a thumb screw threadedly engaged with said spindle tending to force said pulley forwardrand arranged to rotatably retain said spindle in said frame.

j l0. A dental handpiece comprising a frame aording abearing, Ya spindle rotatably mounted in said frame bearing and having a shoulder abutting against said-frame,

a driving cord pulley mounted on said spindle, a collet in threaded engagement with saidspindle, a tool engaging chuck within saidspindle, a. follower for said chuck, vand a chuck rod in threaded engagement with said collet and arranged to actuate said chuck through its follower, said collet being the sole means for holding the spindle, driving 'cord pulley, chuck, follower and chuck rod together.

l1. A dental engine handpiece comprising aV frame, a spindle rotatably mounted inl said frame provided with a shoulder and having a collar arranged to limit the inner movement of said spindle with respect to said frame, a Vdriving cord pulley mounted on said spindle exterior to said frame, athumb screwl threadedly engaged with said spindle ar- 'ranged to retain said driving cord pulley against said shoulder on saidspindle and to prevent the forward displacement of said spindle, a Asheath. forsaid spindle having a lbearing for the forward end thereof, and

means arranged to adjustably engage said sheath toward said bearing to vary the closeness of lit of said bearing. y

l2. A dental engine handpiece comprising a frame, a spindle rotatably mounted in said frame and having a collar arranged to limit the inner movement of said spindle with respeot to said frame, a driving cord pulley mounted .on said spindle exterior to said frame, a thumb screw engaged with' said spindle arranged to retain said driving cord pulley on said spindle, and to prevent the forward displacement of said spindle, a tool holding chuck disposed in the bore of `said.

spindle, a plunger arranged to bear against-l vwith. said spindle tending to force said pulley into position to rotatably retain said spindle in said frame.

`In witness whereof, I have hereunto set my' hand this 16th day of August, A. D. 1928.

l ROBERT C. ANGELL.. 

